I would also say that the MATZ penetration does not allow you into the ATZ.
But, as others have said, if the ATZ penetration is what you wanted, that's what you should have asked for in the first place, and if that's what you do the controller will no doubt be quite explicit in stating whether you've got the clearance you requested. So any discussion about what the controller might mean if you just ask for a MATZ penetration and that's approved should really be nothing more than academic.
FFF
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